Various automated beverages or food dispensers for making hot or cold reconstituted products are known in the art. In a conventional beverage or food dispenser, a metered amount of water-soluble beverage-forming or food-forming powder supplied from a storage canister, and a complementary metered amount of hot or cold water supplied from a water source are mixed to produce a final product, which is dispensed into a cup or glass.
Cohesive and hygroscopic powders, such as milk powders, gravy and other containing fat and/or humectant ingredients, are difficult to dispense out of a beverage or food canister in a consistent manner and are difficult to fully evacuate from the canister. In particular, cohesive powders do not flow well due to compaction and/or decompaction of the powder, lumping, cliffing and bridging inside the canister.
There are mainly two identified issues with dispensing these powders in the traditional canisters.
The first issue relates to the consistency of powder dosing that more particularly refers to the dose-to-dose variation. Typically, the gram-throw of powder dramatically decreases after a certain number of throws and the reconstituted beverage or food becomes more diluted. In terms of product quality, the consistency of the product is important for meeting the satisfaction of the consumer. If the dose-to-dose variation is too large, e.g., on the order of 5% of powder discrepancy or more, it affects the in-cup quality of the product in a way that becomes perceptible for the consumer.
The second issue relates to the powder evacuation out of the canister, which may be incomplete or consistent within a predetermined tolerance. In short, the canister is unable to empty up to a certain point and a significant amount of powder remains. In traditional canisters, powder evacuation includes doses or gram-throws that are below the target throw as well as powder that remains in the canister after the dosing mechanism has stopped delivering powder. In terms of autonomy, low powder evacuation requires the canister to be more frequently filled by the operator, in order for the beverage not to become unacceptably weak when the powder level becomes low. Therefore, such low performing canisters may impact product quality and may require more attention from the operator in re-filling and maintenance of the device.
Current systems typically consist of a single rotary wheel and a breaking mechanism such as wire tapers or springs attached to the wheel. Typical canisters are described in U.S. Pat. Nos. 3,013,701 and 4,207,995.
Dosing is usually performed by an auger, either a spring or screw auger. The dosing end of the canister contains an exit that directs the powder towards the mixing area as it exits. These systems are effective when the powders to be dosed have moderate to good flow properties, but this effectiveness decreases when a poor-flowing, cohesive powder is used.
Furthermore, standard breaker mechanisms consisting of a wheel with tapers, springs or wires which is driven by the auger, while breaking cliffs, tend to sift the powder such that apparent density varies during dispensing. This leads to large fluctuations in the throw weights.
Therefore, there is a need for an improved dispensing canister that provides a better powder dosing consistency and a more complete and reliable powder evacuation than the known canisters of the art, in particular, when using the canister with moderate or bad flowing powders. The present invention now provides such a canister.